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ASADULLAH SHAH BSET-01113049USMAN LATEEF BSET-01113109KHUBAIB UR REHMAN BSET-01113030ADEEL TAYYAB BSET-01113053SIDRA REHMAN BSET -01111058
GROUP MEMBERS
1.Overview about hydroelectric power plant2.Basic principle of hydroelectric power plant3.Historical Back Ground of hydroelectric power plant4.Largest Hydroelectric power Plants in World5.List of Hydroelectric power plants in Pakistan6.Types of Hydroelectric Power Plant 7.Selection of Sight for Hydroelectric Power Plant
8.General arrangement and operation of hydro electric power station9.Mangla dam
10.Advantages and disadvantages
Table of Content
The objective of a hydropower scheme is to convert the potential energy of a mass of water, flowing in a stream with a certain fall to the turbine (termed the "head") , into electrical energy at the lower end of the scheme , where the powerhouse is located. The power output from the scheme is proportional to the flow and the head.
In a Hydro-electric power plant the force is used to drive a turbine, which in turn drives the electric generator. Because gravity provides the force which makes the water fall, the energy stored in the water is called gravitational potential
Basic principle of hydroelectric power plant
HISTORICAL BACKGROUND The mechanical power of falling water is an old resource used for services and productive uses.
Used by the Greeks more than 2,000 years ago.
The first hydroelectric power plant was installed in Cragside, Rothbury, England in 1870.
Industrial use of hydropower started in 1880.
In 1881, a brush dynamo connected to a turbine in a flour mill provided street lighting at Niagara Falls, New York. The world’s first hydro electric station (of 12.5 kW capacity) was commissioned on 30 September 1882on Fox River at the Vulcan Street Plant, Appleton, Wisconsin, USA, lighting two paper mills and a residence .
Largest Hydroelectric plant in world
Hydroelectric plants in Pakistan
OVERVIEW OF POWER SECTOR
Availability of Water Storage of Water Water Head Accessibility to the site Distance from the load Centre Geological Investigation Sedimentation
Selection of Sight for Hydroelectric Power Plant
ADVANTAGES No fuel charges.
Less supervising staff is required.
Maintenance & operation charges are very low.
Running cost of the plant is low.
The plant efficiency does not changes with age.
It takes few minutes to run & synchronize the plant.
ADVANTAGES AND DISADVANTAGES OF HYDROELECTRIC PLANT
No fuel transportation is required.
No ash & flue gas problem & does not pollute the atmosphere.
These plants are used for flood control & irrigation purpose.
Long life in comparison with the Thermal & Nuclear Power Plant.
The initial cost of the power plant is very high.
Takes long time for construction of the dam.
Generally, Such plant’s are located in hilly area’s far away from load center & thus they require long transmission lines & losses in them will be more.
Power generation by hydro power plant is only dependent on natural phenomenon of rain .Therefore at the time of drought or summer session the Hydro Power Plant will not work.
DISADVANTAGES
According to the Quantity of Water :
i. Run off river without pondageii. Run off river with pondageiii. Reservoir or storage power plant
According to the demand of load :i. Base load plant ii. Peak load plantiii. Pump storage power plant for peak load
Types of Hydroelectric Power station
PUMP STORAGE POWER PLANT
According to the Availability of Water Head :HEAD
The head is the vertical distance from the surface of the water at the dam down to the water in the stream below where the turbine is located .
i. Low Head power plant ii. Medium Head power plantiii. Large Head power plant
Available water head is less than 30 meters . Seasonal dam . Lesser power producing capacity.
Low head hydroelectric power plants
Water head is more than 30 meters but less than 300 meters located in the mountainous regions where the rivers flows at
high heights .
Medium head hydroelectric power plants
300 meters and it can extend even up to 1000 meters
most commonly constructed hydroelectric power plants
Water is mainly stored during the rainy seasons and it can be used throughout the year . Thus it can generate electricity throughout the year.
Very important in the national grid because they can be adjusted easily to produce the power as per the required loads .
High head hydroelectric power plants
Catchment area: - The whole area behind the dam draining into streak or river across which the dam is been built at a suitable space is called catchment area.
General arrangement and operation of hydro electric power station
Reservoir
In a reservoir the water collected from the catchment area is stored behind a dam.
Catchment area gets its water from rain and streams. The level of water surface in the reservoir is called Head
water level.
Note : Continuous availability of water is a basic necessity for a hydro-electric power plant.
DamThe purpose of the dam is to store the water and to regulate the out going flow of water. The dam helps to store all the incoming water. It also helps to increase the head of the water. In order to generate a required quantity of power it is necessary that a sufficient head is available
Spillways The rise of water level beyond the limit endangers the stability of dam structure. To relieve reservoir of the excess of after contribution , a structure is provided in the body of dam or near the dam or on the periphery of basin .this safeguarding structure is called spillway.
Gate :A gate is used to regulate or control the flow of water from the dam.
Pressure tunnel:It is a passage that carries water from the reservoir to the surge tank
INTAKEA water intake must be able to divert the required amount of water in to a power canal or into a penstock without producing a negative impact on the local environment .
PENSTOCKConvey water from the intake to the power house . Made of concrete in low heads Made of steel is suitable for all heads
Surge tank:A Surge tank is a small reservoir or tank in which the water level rises or falls due to sudden changes in pressure.
Purpose of surge tank:To serve as a supply tank to the turbine when the water in the pipe is accelerated during increased load conditions and as a storage tank when the water is decelerating during reduced load conditions.To reduce the distance between the free water surface in the dam and the turbine, thereby reducing the water-hammer effect on penstock and also protect the upstream tunnel from high pressure rise.
Water-hammer effect :The water hammer is defined as the change in pressure rapidly above or below normal pressure caused by sudden change in the rate of water flow through the pipe, according to the demand of prime mover i.e. turbine.
After passing through the turbine the water returns to the river trough a short canal called a tailrace.
OUTFLOW / TAILRACE:-
Uses only the velocity of the water to move the runner and discharges to atmospheric pressure.The water stream hits each bucket on the runner. High head, low flow applications.
Types : Pelton turbine, Turgo turbine ,Cross flow
IMPULSE TURBINES
Turgo Turbine
Pelton wheel or Pelton turbine
Combined action of pressure and moving water. Runner placed directly in the water stream flowing over the
blades rather than striking each individually. Lower head and higher flows than compared with the impulse
turbines. Types: Francis Turbine, Kaplan Turbine
Reaction Turbines
FRANCIS TURBINE
KAPLAN TURBINE
KEPLAN TURBINE: Good efficiency range for full and part load condition and
can be operated up to 20% load. Best efficiency=0.91
FRANCIS TURBINE: Full load efficiency is good and part load efficiency is poor
and not recommends operating below 50% load. Best efficiency=0.92 TO 0.94
General Efficiency of Different Turbine:
PELTON TURBINE:∗ Good efficiency range for full and part load condition
and can be operated up to 30% load.∗ Best efficiency=0.90.
General Efficiency of Different Turbine:
TURGO TURBINE:∗ Good efficiency range for full and part load condition
and can be operated up to 25% load.∗ Best efficiency=0.85
General Efficiency of Different Turbine:
∗ If direct drive is required, synchronous speed of generator should be the turbine speed.
∗ Synchronous speed of generator for 50 Hz∗ 12 pole – 500 RPM∗ 10 pole – 600 RPM∗ 8 pole – 750 RPM∗ 6 pole – 1000 RPM∗ 4 pole – 1500 RPM∗ 2 pole - 3000 RPM
Turbine Speed:
BASIC PRINCIPAL
Heart of the hydroelectric power plant .Generator is a device in which when there is rotation of coil between the strong Magnetic Field then it produces an Alternating Current.
GENERATOR
1. Shaft
2. Exciter
3. Rotor
4. Stator
INSIDE THE GENERATOR
TRANSFORMER
.
Its function is to step up the voltage and pass it out to the electrical grid .
The Indus Waters Treaty signed in 1960 India gained rights ( Ravi, Sutlej, Beas rivers) Pakistan received rights( Jhelum, Chenab, Indus river) Jehlam River Constructed between 1961 to 1967 67 miles (108 km) south-east of the Pakistani capital, Islamabad in Mirpur District of Azad Kashmir, Pakistan
MANGLA DAM
The Mangla Dam components includes : Reservoir Main spillwayEmergency spillway 5 tunnels and a power station Switch yard
General arrangement and operation of hydro electric power station
Cost PRs. 6.587 billion (US$ 1.473 billion) The funding being provided by the World Bank and the Asian Development Bank .
CAPACITY1000 MW with 15 % over load that is allowed by designer i .e 1150MW .After up gradation …………….. 1350 MW
ORIGINAL Raised
Maximum Conservation Level
1202 ft (366.5 m) 1242 ft (378.7 m)
Minimum Operation Level 1040 ft (317.1 m) 1040 ft (317.1 m)
Area 100 Sq Mile (259 Sq Km) 125 Sq Mile (324 Sq Km)
Capacity 5.88 MAF (Million Acre-feet)
7.39 MAF (Million Acre-feet)
Reservoir
MAIN COMPONENTS ORIGINAL RAISED
Main Dam and Intake Embankment
Maximum Height 454 ft (138.4 m) 484 ft (147.5 m)
Crest Length 10,300 ft (3,140 m) 11,150 ft (3,400 m)
MAIN COMPONENTS ORIGINAL RAISED
Main Spillway Maximum Discharge Capacity
1,010,000 cusecs same as original
Power TunnelsNo of Tunnels Five same as original
Inner Diameter 26 ft to 31 ft (7.9 to 9.4 m) same as original
Lining Concrete / Steel same as original
Length 1,560 ft (476 m) same as original
MAIN COMPONENTS ORIGINAL RAISED
Power Station
No of Generating Units 10 (Two on each Tunnel) same as original
Installed Capacity (100 MW x 10 Units)
1000 MW same as original
MANGLA SPILLWAYS
• 9 gates• 36 ft wide and 40 ft high(each)
TURBINES USED IN MANGLA 10 number of turbine Francis turbine vertical shaft Reated Head 295 ft1~4 1969 (Mitsubishi,Japan)5~6 1974 (CKD Blansko,Czech)7~8 1981 (Escherwyse-ACEC,Belguim)9~10 1994 (SKODA,Czech)
Generators in MANGLA
10 number of generators coupled with turbine 13.2 kv produced by each generator 166.7 RPM 100 MW of each unit 1~4,7,8 (Hitachi,Japan) 5,6,9,10 (Skoda,Czech)
SYNCHRONIZATION OF GENERATOR
TRANSFORMER
• 13.2 kv is step up to 132 kv and 220 kv .• 1~2=13.2kv/132kv• 4~10=13.2kv/220kv
SWITCH YARD
9 feeders of 132 kv3 feeders to Rawalpindi3 feeders to kharian 1 feeder to Meer pur2 feeders to Sucraat
6 feeders of 220 kv 4 feeders attached to Kala shah kaku2 feeders attached to TARBAILA
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